Kiddushin 77 - Kosher Kohen
A child born from a union between a Kohen and a woman who is forbidden to him due to his status as a Kohen is not imbued with Kohanic sanctity. He may not perform the Temple service and he is not subject to the prohibition against going to the cemetery.
Women prohibited to a Kohen include a divorcee, a convert, and a woman who cohabited with any man whom she is Biblically forbidden to marry.
If a male convert marries a female convert, their daughter is allowed to marry a Kohen.